Study Finds Miscarriage Treatment May Actually Be Harmful
Many women being treated for recurring miscarriages with a therapy called mononuclear-cell immunization are actually being put at greater risk of miscarriage, according to an American and Canadian team. About 15% of pregnancies confirmed by a doctor are spontaneously aborted, making miscarriage the most common complication of human pregnancy.
In most women who suffer recurrent miscarriages, no obvious cause is apparent. One theory is that the woman’s immune system is reacting to fetal proteins originating from the father’s genes--in effect, rejecting the fetus. Researchers have attempted to overcome this theoretical problem by immunizing the woman with tissues readily obtainable from the father, a form of white blood cell called a mononuclear cell. Although the technique is still relatively rare, it is being used at a growing number of reproductive-health facilities.
Earlier studies of the technique have produced equivocal results, but the newest one, reported in Saturday’s Lancet, indicates that it is not beneficial and may even be harmful.
A team headed by Dr. Carole Ober of the University of Chicago enrolled 179 women who had suffered at least three miscarriages, had given birth to no more than one child and who were under the age of 40. About half were immunized with mononuclear cells from the father and half with saline solution.
The team found that 68 of the treated women and 63 of the control group conceived within 12 months of the immunization. Among the women receiving the father’s cells, 37 (54%) suffered a miscarriage, compared with 22 (35%) in the control group. An independent safety monitoring committee then recommended that the study be halted because of the increased risk of miscarriage.
Walking May Sharpen Seniors’ Mental Acuity
Walking can improve the mental abilities of the elderly, even if they have been couch potatoes all their lives, according to researchers from the University of Illinois. The team thinks that extra oxygen taken in during the exercise improves reaction times in the frontal areas of the brain and heightens the ability to ignore distractions.
Psychologist Arthur F. Kramer and his colleagues studied 124 adults, ages 60 to 75. About half did toning exercises (anaerobic activities) and half walked. The latter group started out walking for 15 minutes at 17.7 minutes a mile, three times a week, and eventually reached 16-minute miles for 45 to 60 minutes three times a week.
The team reported in Thursday’s Nature that those who walked were better at completing relatively complex mental tasks than were those who did the toning exercises. The walkers’ oxygen intake, moreover, improved by about 5%.
Test Compares L-dopa and Parkinson’s Drug
Treating Parkinson’s disease patients with a relatively new drug called Requip and delaying the use of L-dopa as long as possible can reduce the incidence of involuntary muscle movements, researchers from the University of Pennsylvania reported Tuesday. L-dopa, which has been approved for 35 years, is the gold standard for treatment of Parkinson’s disease and is highly effective at controlling symptoms in the early stages. But many users develop involuntary muscle movements that can prevent them from such activities as sitting in a chair and eating.
Requip, known generically as ropinarole, was approved two years ago. It is not as effective as L-dopa but produces fewer side effects.
Dr. Matthew B. Stern and his colleagues studied 130 Parkinson’s patients for five years. Half were started on L-dopa and half were started on Requip, proceeding to L-dopa only when control of symptoms required it. The team told a Parkinson’s conference in Vancouver on Tuesday that only 5% of those started on Requip suffered involuntary muscle movements during the course of the study, compared with 36% of those who started on L-dopa.
Discovery Gives Insight Into Preeclampsia
Women who suffer from preeclampsia, a potentially fatal complication of pregnancy, have an imbalance in two key chemicals that are involved in regulating blood pressure, according to researchers from the National Institute of Child Health and Human Development. The chemical imbalance precedes the symptoms of preeclampsia by several months.
The findings suggest new ways to treat or prevent the disorder, which affects about 5% of first-time mothers and 1% to 2% of those having subsequent pregnancies. Preeclampsia may progress to eclampsia, which is marked by high blood pressure and convulsions. Children of mothers with preeclampsia are often small for their gestational age or born prematurely. There is no cure for the disorder.
Dr. James L. Mills and his colleagues studied the medical records of 2,294 women who participated in an earlier trial that showed calcium supplements do not prevent preeclampsia. They reported in Wednesday’s Journal of the American Medical Assn. that among the 134 women who developed preeclampsia, all had unusually low levels of a substance known as prostacyclin, or PG12, and relatively high levels of another chemical, thromboxane.
PG12 causes blood vessels to relax, reducing blood pressure, while thromboxane causes them to constrict, raising it. Treating pregnant women with PG12 or related compounds might reduce preeclampsia, the researchers speculated.
Antibiotic Promising for Muscular Dystrophy
Treatment of some muscular dystrophy patients with the antibiotic gentamycin might be able to arrest the course of the disease, according to studies on mice by researchers from the University of Pennsylvania Medical Center. The treatment could be useful in the 15% of patients with a specific defect in the gene for the protein dystrophin. The defect, called a “premature stop codon,” causes the disease by telling the cell’s protein-making machinery to stop prematurely during the construction of dystrophin, leading to a nonfunctional protein.
Studies in mice that are genetically engineered to have the specific mutation show that treatment with gentamycin allows the protein-making machinery to “read through” the stop codon and produce a complete protein, the team reports in the Aug. 15 issue of the Journal of Clinical Investigation. They hope to begin testing the therapy in humans this year.
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Thomas H. Maugh II can be reached by e-mail at thomas.maugh@latimes.com.
